Cilostazol.

Cilostazol is an antiplatelet agent with vasodilating properties that has been used in the treatment of patients with peripheral ischaemia such as intermittent claudication. The drug inhibits platelet aggregation induced by ADP, collagen and arachidonic acid. Unlike aspirin (acetylsalicylic acid), cilostazol inhibits both primary and secondary aggregation. It also acts as a vascular vasodilator by inhibiting calcium-induced contractions while having no direct effect on contractile proteins. In double-blind randomised trials, patients with intermittent claudication receiving cilostazol showed significant improvements versus placebo in terms of time to initial pain and maximal walking or absolute claudication distance; these findings were confirmed by cilostazol patients' positive responses on subscales measuring physical functioning and quality of life. In a 24-week randomised double-blind trial in patients with intermittent claudication, cilostazol 100mg twice daily produced significant improvements in pain-free and maximum walking distances, compared with pentoxifylline (oxpentifylline) 400mg 3 times daily and placebo. Cilostazol has been well tolerated, with the most common adverse events being headache, diarrhoea, abnormal stools and dizziness.